Tilt control device for an outboard motor



F. T. IRGl-:Ns 2,961,207

TILT CONTROL DEVICE FOR AN OUTBOARD MOTOR Nov. 22, 1960 Filed Jan. 29, 1958 AT TO RNE YS United States Patent O TILT CONTROL DEVICE FOR AN OUTBOARD MOTOR Finn Irgens, Wauwatosa, Wis., assigner to Outboard Manne Corporation, Waukegan, Ill., a corporation of Delaware Filed Jan. 29, 1958, Ser. No. 711,996

10 Claims. (Cl. 248-4) This invention relates to a tilt control device for an outboard motor.

Propulsion units of outboard motors are usually mounted in a transom bracket by means of a horizontal pintle which allows pivotal movement of the propulsion unit in a vertical plane both for the purpose of adjusting it to the desired position of operation and for the purpose of allowing it to tilt in traversing submerged objects. Forward thrust has been taken by a thrust block adjustable respecting the transom bracket and from which the propulsion unit is tiltable more or less freely except during reversal, when a lock becomes effective to hold the propulsion unit to the thrust block. Reverse lock control has the disadvantage that when the lock is disengaged either during normal operation or as the result of breakage, the tilting of the motor is completely unrestrained.

With the advent of outboard motors having more powerful engines, it has become desirable to provide other means of controlling tilting. Especially, it is desirable to provide a tilting control which is continuously effective to provide impositive resistance to tilting oscillation of the propulsion unit in all positions thereof. The present invention contemplates the provision of a support member angularly adjustable respecting a boat-applicable mounting and with respect to which the propulsion unit is independently tiltable subject to the control of means offering continuous but yielding opposition to tilting movement, and having suicient resistance to provide for normally holding the propulsion unit in any desired position. ln prior art devices, the tilting movement has been uncontrolled.

Various energy absorbing devices are usable to resist tilting of the proulsion unit from the position to which it is adjusted on the mounting means. A friction clutch is the chosen exemplitication.

In practice, the support member preferably comprises a pintle subject to controlled rotative adjustment on the mounting bracket to carry the propulsion unit with it to any desired position of tilt, the independent tilting of the propulsion unit respecting the pintle being co-ntrolled by a friction clutch. In order to permit of intentional tilting o-f the propulsion unit notwithstanding its weight, reduction gearing is desirably provided to be operated either manually or by power for adjusting the pintle to any desired position. Since the friction clutch device is effective between the horizontal pintle and the propulsion unit, any rotative adjustment of the pintle will carry the entire propulsion unit with it to the desired position.

In the drawings:

Fig. l is a side elevation of the outboard motor embodying the invention, as applied to a boat transom, the transom and portions of the motor being shown in section.

Fig. 2 is a detail view on an enlarged scale taken in Section on the line 2-2 of Fig. l.

Fig. 3 is a view in cross section on the line 3-3 of Fig. 2.

Fig. 4 is a fragmentary detail view similar to a por--k tion of Fig. 2 but illustrating a hand crank substitute for the vmotor as a means of tilting the propulsion unit.

The propulsion unit 5 may, for the purposes of the present invention, be of any desired type o-r construction, It comprises a power head (engine) 1, a lower unit or gear housing 2 which carries t-he propeller shaft 3 and propeller 21, and a strut dwhich connects the power head and lower unit and through which extends the drive shaft from the engine to the propeller shaft 13. The lower unit 2 is conventionally provided with a skeg 14. The transom bracket 6 may also be conven-V tional. As shown, it is attached to the boat transom 8 in the usual manner by manually operable set screw means 7.

The bracket 6 may carry any simple, adjustable thrust receiving member 24, normally abutted by the upright propulsion unit to transmit to the boat the forward propulsive thrust developed by the engine driven propeller.

No reverse lock is required because of the invention here` inafter described.

Referring to Fig. 2, the two sides of the channelshaped transom bracket 6 are designated at 11 and 12.

The sleeve 10 constitutes a pintle extending betweenv vided by the transom bracket arms 11 and 12. To loier.

yielding opposition to the tilting of the propulsion unit independently of the pintle, a friction clutch is providedl in this embodiment of the invention.

Splines 16 and 17 respectively formed interiorly in the bearing element 15 of arm 9 and externally on the sleeve 10 are engaged in notches of friction clutch disks 18, 19. Compression springs 2G centrally disposed act oppositely to force the two sets of disks 18 and 19 into pressure engagement of their faces to provide frictional resistance to rotative movement of bearing member 15 respecting pintle tube 19. The terminal plates 22 and 22' against which the clutch disks are urged by springs 20 provide bearing support for bearing 15 from the pintle sleeve 1t), whereby bearing member 15 and the propulsion unit can be tilted with respect to the pintle sleeve subject to the frictional resistance of the clutch disks.

The clutch action is adequate to fhold the propulsion unit angularly fixed respecting the pintle against any force exerted by the propeller 21 during reverse operation thereof by the engine power head 1. The clutch friction is not necessarily relied upon to withstand the full power of the propeller thrust during forward pro-I pulsion, since the ordinary thrust transmitting member'` 24 adjustably connected with the transom bracket may be used for this purpose if desired. The `clutch friction should not be so great as to preclude the tilting of the propulsion unit in the event that the propeller strikes a submerged obstacle, such as a shoal or rock.

The pintle 10 constituting the propulsion unit support not only accommodates tilting movement of sion unit but is itself rotatably adjustable. For tilting adjustment of the propulsion unit to its normally erect position, and for tilting the propulsion unit from and to that position, as may be desirable, for example, in beaching the boat, it is not necessary to overcome the resistance offered frictionally by the clutch. instead, means is provided for rotating with respect to the transom bracket the horizontal pintle with which one set of clutch elements is connected. The rotation of the hori- Patented Nov. 22, 1960H the propulzontal pintle will necessarily operate through the clutch to effect the corresponding movement of the entire pro'- pulsion -unit in a tilting direction.

In order to facilitate such adjustments, a powerful reduction gearing is provided for power of manual. operation to elect relative rotating movement of the pintle. The'shaft 25 within the tubular pintle 10 may be driven either bymeans of a motor 26 or'h'and crank 27 as shown in Figs. 2 and 4, respectively. The shaft 25 acts through reduction gearing which here constitutes a double planetary gear set to rotate the pintle to any desired position, carrying with it the entire friction clutch and the bearing and arm`9 and propulsion unit.

Keyed to the righthand end of drive shaft as viewed in Fig. 2, is the hub of a planetary pinion carrier in which are mounted pairs ofv interconnected pinions 31, 32. Pinions 31 mesh with a ring gear 33 fixed between the parts 34, 35 of planetary gear case generically designated by reference character 36. Pinions 32mesh with the ring gear 37 connected to another planetary pinion carrier38 which is rotatable on the bushing 39. Mounted in the carrier 38 are pairs of interconnected planetary pinions 4l)i and 41. The pinions 49 mesh with ring gear 42 Vwhich is fixed to the part 35 of gear casing 36. Pinions V41 mesh with ring gear 43 which is attached to lche end of the pintle tube 10.

The successive planetary gear set ratios will be described only by way of exemplication. The pinions 31, 32 each have twelve teeth. The ring gears 33 and 37 with which these pinions respectively are meshed have forty teeth and thirty-nine teeth, respectively. Therpinions and 41 each have nine teeth and the ring gears 42 and 43 with which they mesh are respectively provided with thirty teeth and twenty-nine teeth. The overall reduction `in the operation of these successive gear sets is 1200 to l. Hence the pintle 10 will maintain any position to which it is rotated through these gear sets and the propulsion unit will take its position of tilt accordingly.

The propulsion unit is subject, however, to tilting displacement from its normal upright position when any submerged obstacle is encountered. The friction oiered by the clutch determines the resistance oiered continuosly to tilting of the propulsion unit. It is not involved in the movement of parts for initial adjustment purposes or for manually controlled tilting, since the pintle and the Yclutch and the arm 9 and the propulsion unit all move bodily as a unit about the axis of pintle 19 subject to the control of the reduction gear set. However, in the event that the skeg of the propulsion unit encounters a submerged obstacle, the resulting tilting of the unit is not a free tilting, such as might occasion shock or damage. On the contrary, the impositivo frictional resistance offered by the Vclutch continues until the tilting of the propulsion unit is checked.,

I claim:

1. In a marine propulsion mechanism, the combination with a mounting member and a propulsion unit, of means for tiltably supporting the pro-pulsion unit on the mounting member, an energy absorbing device connected between said' propulsion unit and said means and effective for resisting movement of the pro-pulsion unit in the plane in which tilting occurs respecting said member, and mechanism'for tilting said device and unit bodily Y respecting said member to a predetermined pofition from which said unit is independently tiltable subject to the control of said device.

2. The device of claim l in which said energy absorbing device comprises a friction clutch.

3. The device of claim 1 in which the means tiltably supporting the propulsion unit has bearings on which it is carried for rotation on the mounting member.

4. The device of claim 3 in which the means tiltably supporting the propulsion unit comprises a pintle having inlinite rotation respecting the mounting memberthe said mechanism for tilting said device and unit bodily comprising means for effecting the rotation of the pintle respecting said mounting member and eifective through said movement resistingnieans to determine the tilted position of the propulsion unit.

5. In a marine propulsion mechanism, the combination with a mounting device, of a support having means connecting it to the mounting device for rotatable adjustment respecting the mounting device, a tiltable propulsion unit having means connecting it to the support for tilting movement respecting the support, said last means comprising means for resisting tilting movement of the propulsion unit respecting the support, and means for rotatably adjusting the support to adjust the initial position of tilt of said propulsion unit.

6. The device of claim 5 in which the means for rotatably adjusting the support comprises a high reduction gear set having a driven element connected with the support.

7. The combination set forth in claim 6 in which .the mounting device comprises a transom bracket having transversely aligned bearings and the support comprises a pintle rotatable in said bearings, the propulsion unit having bearing means tiltable substantially coaxial with the pintle and the means for resistingtilting movement comprising clutch elements respectively connected with said bearing means and said pintle.

8. The device of claim 7 in which said gear set is planetary and has a driving shaft extending through the pintle, the pintle being tubular. I

9. In a marine propulsion mechanism, the combination with a transom bracket and a propulsion unit having an arm provided with a bearingrportion; of means for mounti ing the propulsion unit on the transom bracket, said means comprising a pintle for which the transom bracket provides bearings and 'which isenciicled by said bearing. portion, means rotatably supporting said bearing portion from said pintle, clutch disks alternately connected with said bearing portion and pintle and disposed within the bearing portion and about the pintle, means for exerting clamping pressure on said .clutch disks in. a direction generally axial or said pintle to engage their faces f rictionally with each other, the clutch disks having sucierit frictional resistance to maintain the propulsion uint normally in predetermined position of tilt respecting the pintle while accommodating'tilting movement of the propulsion unit when the Vlatter is subjected to abnormal conditions, and means forcontrolling the tiltable position of the propulsion unit and said pintle with respectto the transom bracket, said means including `a reduction gear set mounted on the transom bracket and having driving and driven members, the latter being connected to said pintle forkthe rotation thereof in the transom bracket bearing. i 1

l0. The device ofclaim 9 in which said pintle is tubular, thedriving member comprising `a drive shaft extending through the pintle, and the reduction gear set compries a planetary transmission having a driving planetary pinion carrier connected with the drive shaft, planetary pinions operatively mounted ,on .the carrier, and a driven ring gear meshing with said pinlons` and opera tively connected with said pintle.

References Cited in the tile of thisrpatent FOREIGN PATENTS Y '568,341 yGreat Britain Mar. 29, 1945 

